clock() linux

#include <iostream>
#include <ctime>

int main() {
    clock_t start = clock();

    // 模拟一些计算密集型任务
    for (int i = 0; i < 1000000; ++i) {
        // 做一些计算
    }

    clock_t end = clock();
    double time_spent = static_cast<double>(end - start) / CLOCKS_PER_SEC;

    std::cout << "Time spent: " << time_spent << " seconds" << std::endl;
    return 0;
}

#include <iostream>
#include <chrono>

int main() {
    auto start = std::chrono::high_resolution_clock::now();

    // 模拟一些计算密集型任务
    for (int i = 0; i < 1000000; ++i) {
        // 做一些计算
    }

    auto end = std::chrono::high_resolution_clock::now();
    std::chrono::duration<double> elapsed = end - start;

    std::cout << "Elapsed time: " << elapsed.count() << " seconds" << std::endl;
    return 0;
}

#include <iostream>
#include <thread>
#include <vector>
#include <chrono>

void worker() {
    auto start = std::chrono::high_resolution_clock::now();
    // 模拟一些计算密集型任务
    for (int i = 0; i < 100000; ++i) {
        // 做一些计算
    }
    auto end = std::chrono::high_resolution_clock::now();
    std::chrono::duration<double> elapsed = end - start;
    std::cout << "Thread time: " << elapsed.count() << " seconds" << std::endl;
}

int main() {
    const int num_threads = 4;
    std::vector<std::thread> threads;

    for (int i = 0; i < num_threads; ++i) {
        threads.emplace_back(worker);
    }

    for (auto& t : threads) {
        t.join();
    }

    return 0;
}